Magnetically controlled applicator



April 11, 1961 c. L. HOPKINS 2,978,723

MAGNETICALLY CONTROLLED APPLICATOR Original Filed Dec. 30, 1955 I N V EN TOR. C EC/L L HOD/(INS Sci/1401x4491 Mnawfid/ 4 TTOENE 7 5 Original application Dec. 30, 1955, Ser. No. 556,631,

now Patent No. 2,849,738, dated Sept. 2, 1958. Divided and this application May 21, 1958, Ser. No.

12 Claims. (Cl. 15-537) This invention relates to liquid applicator devices of the type in which a brush or other yieldable liquid applying element is stored interiorly of an hermetically sealed container for the liquid, and the container has a discharge opening which is unsealed and through which the brush or applying element is projected for use.

In applicators of the character referred to it is desirable to provide means for holding the brush in projected use position so that the brush is not forced back into the container by the slight endwise pressure which is incidental to using the brush in applying the liquid. In one type of well-known applicator, shown and described in United States Patent 2,485,494, issued October 18, '1949, to Harry W. lockers on Gravity Controlled Liquid Applying Device, the brush is carried by a weighted stem so that by removing the sealing cap and then pointing the nozzle downwardly the weighted stem drops by gravity and projects the brush through the discharge opening for use. When such an applicator is turned to a position in which the discharge opening is pointed upwardly the brush is drawn into the container by the dropping of the weighted stem. The gravity controlled applicator as previously known is thus unsuited to uses such as painting or touching up an undersurface on an appliance, automobile or article of furniture.

In the case of an applicator having a spring or other resilient means biasing the brush and stem to the projected use position, such as described and claimed in copending application for patent Serial Number 379,851, filed September 14, 1953, for Fountainbrushes for Mobile Material, it is desirable, particularly with a stiff brush, to provide means other than the spring for re taining the brush in the projected position.

It is, therefore, the aim and objective of the present invention to provide improved means for holding the liquid applying brush or element in projected use position in applicator devices of the type referred to. This objective is achieved by incorporating magnetic elements in the device, one carried by the container and the other carried by the stem or movable liquid applying component. These magnetic elements are so arranged that when the liquid applying brush is in projected use position the lines of force between the magnetic elements resist return movement of the brush to the retracted or nonuse position within the container. As another aspect of the invention the magnetic elements are so arranged that the magnetic lines of force bias the brush to projected use position and thus augment the force of gravity in the case of a gravity actuated device or the force of the projection spring in the case of a spring actuated device in moving the brush to projected use position.

alent The present application is a division of my copending application for United States patent, Serial Number 556,631, filed December 30, 1955, now Patent 2,849,738, dated Sept. 2, 1958, for Retractable Brush Applicator with Magnetic Brush Retainer. The best known mode 2,978,723 Patented Apr. 11, 196i part of the specification.

In the drawings:

.Figure 1 is a fragmentary longitudinal sectional view' of the nozzle end of a gravity controlled applicator in which a brush-carrying assembly having a nonmagnetic stem is fitted with a magnetic element to coact with a magnetic element held fast on the nozzle body so as to influence the steel brush-carrying stern toward projected use position and to hold the stem and brush so projected; v

Fig. 2 is a transverse section through the applicator of Fig. 1, being taken substantially in the plane repre sented by the line 2-'2 of that figure;

Fig. 3 is a fragmentary longitudinal sectional detail, similar to Fig. 1 showing a modification in which the magnetic element carried by the nonmagnetic brush assembly is influenced by a sleevelike magnetic element disposed in the liquid passage of the nozzle body, which latter element has a flange held fast between a shoulder of the nozzle body and a metering washer which loosely surrounds the brush stem and which washer has an outer periphery in strong frictional engagement with the internal walls of the nozzle body; and a Fig. 4 is a transverse sectional detail taken substam tially in the plane represented by the line 4-4 of Fig. 3.

The present invention is of utility in applicators having containers of various shapes and constructions but, for simplicity, is illustrated in connection with applicators having containers comprising a receptacle 1 con.- veniently formed of aluminum as by drawing into substantially cylindrical tube shape. The tubular receptable receives as by a sealing press fit the generally cylindrical end 3 of a tubular nozzle member 4 molded of a suitable nonmagnetic material such as phenolformaldehyde, a urea resin or a hard plastic composition. Extending axially through the circular sectioned nozzle body is a passage 5 for the liquid which accommodates an axially movable brush assembly comprising a stem and a brush 7. The stem is formed of plastic or other nonmagnetic material having an elongated rod portion 55 and a cylindrical brush carrying portion 56. The bristles of brush 7 are embedded in a plastic base 10 press fitted into a cylindrical end recess in the holding portion 56. Radial cars 57 molded integrally on the brush holding portion 56 have their ends disposed for sliding engagement with the cylindrical walls of the internal fiuid passage 5 so as to guide the brush stem for endwise movement on the axis of the nozzle between projected and retracted brush positions.- Outer end portion 11 of the nozzle body member 4 is tapered and terminates in a discharge opening 12 through which the brush is projected for use and through which liquid flows onto the brush when the device is being used to apply the liquid to the surface to be covered.

When the device is not in use the discharge opening 12 is sealed by a conventional thimblelike cap (not shown) which is received over the nozzle member 4 and held in place as by a threaded joint comprising internal threads in the skirt portion of the cap and external threads 16 on the nozzle body adjacent the base of the latter. A circular disc of deformable plastic material such as polyethylene is retained in a recess in the bottom of the closure cap and is engaged by tip end 19 of the nozzle body to seal the discharge opening when the closure is tightened in place.

In the enlarged circular sectioned chamber or counterof practicing the principles of. the .invention is illusa fiat, arcuately curved split ring magnet 53 having its outer periphery seated against a circular shoulder 59 at the end of the counterbore 24. A circular split spring 'normal use.

ring 60 is received in the counterbore 24 outwardly of the magnet 58 and expands, the inherent resiliency of the spring ring expanding it against the walls of the counterbore and thereby holding it and the magnet in place byfriction. Desirably an annular groove 61 is formed in the counterbore to receive the spring locking ring 66. The inner periphery 62 of the circular washer magnet 53 is spaced from the plastic rod portion 55 of the brush stem in the provision of an annular clearance 63 con tinuous with the radial slot between magnet pole ends 68, 69. The clearance and slot together constitute a metering orifice through which the liquid is metered into the main portion of the nozzle chamber 5.

When the cap is removed and the applicator device inverted, the weight of the brush assembly causes such assembly to move downwardly by gravity to the use position shown in Fig. l, projecting the brush 7 through the discharge opening 12 and bringing circular edge corner 66 on the end of the stem portion 56 into circular line contact sealing engagement with a tapered frustoconical wall portion 21 of the nozzle body passage adjacent the discharge opening. In this endwise travel of the brush assembly projecting the brush, and likewise in reverse travel retracting the brush, the rod portion 55 of the stem is guided by the fiat circular magnet 58. The enlarged passage portion 24 opens through the base end of the nozzle body and constitutes the fluid receiving opening of the nozzle. The magnet 58 embraces and guides the stem of the valve assembly and controls the flow of the liquid into the nozzle chamber from the main supply receptacle.

The rod portion 55 of the brush stem disposed on the outside of the nozzle chamber carries a sleeve 65 of magnetic material such as soft iron or cold rolled steel which is suitably held in place on the stem as by being press fitted. The sleeve 65 is located on the stem so that when sealing edge corner 66 of the brush holding portion 56 of the stem makes circular line contact seal with the frustoconical seat portion 21 of the nozzle'passage, inner "end 67 of the iron sleeve 65 is located closely adjacent to the magnet 58 so as to be strongly attracted by the mag netic lines of force which travel through the end of the iron sleeve 65 between poles 68 and 69 of the magnet. The magnet 58 takes the form of a circular split ring of high magnetic coercive force. This magnet may comprise any of the high efiiciency ferrous alloy metals, such as the aluminum-nickel-iron alloys or a powdered metal magnet having the desired high coercive force. Because of the relatively small size of the applicatonthe circular sectioned nozzle having an external diameter of the order of about inch, the magnet element is necessarily very small, thus requiring a magnet of high coercive force to hold the brush assembly in projected position during The stem sleeve 65 provides a low reluctance path for the magnetic lines of force extending between the opposite poles 68, 69 of the magnet. Thus the magnetic attraction which exists between the poles of the magnet and the soft iron or steel of the brush assembly sleeve 65 resists endwise movement of the brush assembly away from the projected use position.

With the brush assembly shifted by gravity to the projected use position, the magnetic lines offorce acting between the magnetic iron of the stem sleeve 65 and the magnet 58 fast in the nozzle body resist endwise displacement of the brush assembly from projected use position to permit upending of the applicator in painting the undersurface of an appliance, article of furniture or vehicle. In such case the gap between the ends of poles 68, 69 of the magnet is of the order of about inch, although, of course, wider gap-s may be employed. Although the biasing force of the magnetic attraction between the elements is sufiicient to permit use of the applicator with the brush directed upwardly and also to prevent unseating of the circular valve corner 66 in normal painting useon a fiat-surface, it is feasible by manipulating the device so as 4 to exert direct endwise pressure on the bristles of the brush 7 to shift the brush assembly axially sufficient to unseat the valve edge corner 66 and permit a quantity of liquid to flow out the discharge opening 12 of the nozzle onto the still projected brush 7.

After a period of use or when otherwise it is desired to retract the brush into the nozzle, the device is upended and the stem element 65 is removed from the effective retaining force of the magnetic element 53 by tapping the closed end of the receptacle. As soon as the brush stem is thus released from the retaining influence of the magnet the brush assembly drops by gravity to the retracted position, permitting the sealing cap to be replaced over the nozzle.

Fig. 3 illustrates a variation of the applicator device shown in Figures 1 and 2. In the Fig. 3 arrangement an annular sleeve magnet 70 is received within the base end of the nozzle, the magnet having an easy sliding fit in the cylindrical bore or chamber 5. Suitable means is provided for locating the magnet axially in the nozzle chamber, such as cement or, as shown, the magnet may be formed. at its outer end with an annular radial outwardly projecting flange 71 that engages the radial shoulder 59 at the end of the enlarged counterbore portion 24 in the base end of the nozzle. A circular plastic metering washer 23 is received in the nozzle base chamber 24 against the outside end face or pole 71 of the axially polarized magnet 70. The tight frictional fit of the plastic metering washer 23 in the chamber or counterbore 24 retains the washer in place and, in cooperation with the shoulder 59 in the base of the nozzle, holds the magnet in'predetermined axial position.

Since, as mentioned above and as shown in Fig. 4, the magnet 70 is in the form of a completely annular sleeve,

it is polarized axially, one pole, say the north pole, being at the upper end and the other, or south pole, being at the lower end. When the brush assembly is moved as by gravity to the projected use position, lower end 67 of the element 65 of iron or other magnetic material is located closely adjacent the face of the metering washer 23 so that the lines of magnetic force from the circular pole of the magnet 70 act on the sleeve 65 through a relatively narrow gap.

In assembling the soft iron sleeve 65 on the plastic rod portion 55 of the brush assembly the sleeve is so located or positioned that when the edge corner 66 at the brush end of the stem is in sealing engagement with the tapered valve seat 21 a slight gap or clearance re mains between the metal sleeve end 67 and the metering washer 23. This gap prevents engagement between the magnetic sleeve element and the plastic washer, which might hold the far end of the brush stem away from the nozzle body valve seat, thereby insuring positive seal of the discharge outlet at the tip end of the nozzle body by the end corner 66 of the brush stem.

The present invention'thus provides magnetic elements in combination in a liquid applicator of the type in which a brush assembly comprising an elongated stem and a tuft of bristles on one end of the stem is movable axially through the bore of a tubular nozzle. Movement in one, or the forward, direction projects the brush bristles or tuft through the axial discharge opening in the tip end of the nozzle body to a position of use, and movement in the other, or reverse, direction withdraws the brush tuft into. the interior of the nozzle so that a sealing cap can be applied against the discharge opening. Magnetic elements, one on the brush assembly and one on the nozzle body, are so arranged that the magnetic lines of force between them tend to hold the brush assembly with the tuft of bristles in projected use position. Although in each of the several embodiments described the magnetized element is carried by the nozzle body and the soft iron or armature element of the magnetic combination is carried by the-stem, it is contemplated that the parts may be reversed so that the magnet is carried by the stem and the soft iron armature is carried by the nozzle body.

In accordance with the patent statutes the principles of the present invention may be utilized in various ways, numerous modifications and alterations being contemplated, substitution of parts and changes in construction being resorted to as desired, it being understood that the embodiments shown in the drawings and described above are given merely for purposes of explanation and illustration without intending to limit the scope of the claims to the specific details disclosed.

What I claim and desire to secure by Letters Patent of the United States is:

1. A liquid applicator of the retractable brush type comprising a hollow container having a neck formed with an outlet through which liquid is dispensed from the interior of the container; a tubular nonmagnetic nozzle body fast to the container and having an axial through passage, the passage having an inner end opening continuous with the neck outlet and an outer end discharge opening; a brush assembly disposed in the nozzle passage, said brush assembly comprising an elongated stem of nonmagnetic material, a brush tuft mounted on and projecting axially from one end of the stem, and a tubular sleeve element of magnetic material tightly embracing the stem in surrounding relation to and intermediate and spaced from both ends of the latter for movement therewith; the brush assembly being axially shiftable in the nozzle passage between a use position in which the brush tuft projects from the discharge opening and a storage position in which the brush tuft is retracted, and a magnetic ring element carried by the nozzle body, said ring element being in surrounding relation and coaxial to the stem, one of the magnetic elements being magnetized to influence the axial position of the brush assembly in the nozzle passage.

2. A liquid applicator of the retractable brush type comprising a hollow container having a neck formed with an outlet through which liquidis dispensed from the interior of the container; a tubular nonmagnetic nozzle body fast to the container and having an axial through passage, the passage having an inner end opening continuous with the neck outlet and an outer end discharge opening; a brush assembly disposed in the nozzle passage, said brush assembly comprising an elongated stem of nonmagnetic material, a brush tuft mounted on and projecting axially from one end of the stem, and a tubular sleeve element of magnetic material tightly embracing the stem in surrounding relation to and intermediate and spaced from both ends of the latter for movement therewith; the brush assembly being axially shiftable in the nozzle passage between a use position in which the brush tuft projects from the discharge opening and a storage position in which the brush tuft is retracted, an arcu-ately curved element of magnetic material carried by the nozzle body and substantially completely surrounding the stem, one of the magnetic elements being magnetized so as to influence the other, and the elements being respectively positioned on the stem and nozzle so that in the projected use position of the brush tuft the magnetic lines of force between the elements resist movement of the brush assembly to retracted position.

3. A liquid applicator of the retractable brush type comprising a hollow container having a neck formed with an outlet through which liquid is dispensed from the interior of the container, a tubular nonmagnetic nozzle body fast to the container and having an axial through passage, the passage having an inner end opening continuous with the neck outlet and an outer end discharge opening, a brush assembly disposed in the nozzle passage, said assembly comprising a generally nonmagnetic stem, a magnetic metal element in the form of a tubular sleeve mounted on an intermediate portion and spaced from both ends of the stem at the inner end of the nozzle, and a brush mounted on the stem at the outer end of the nozzle, the brush assembly being axially shiftable in the nozzle passage between a use position in which the brush projects from the discharge opening and a storage position in which the brush is retracted wholly within the nozzle passage, the nozzle passage including an enlarged portion at said inner end in the provision of an annular radial shoulder, an element of magnetic material surrounding the stem and disposed against said shoulder, one of said magnetic elements being magnetized to attract the other, and the magnetic element on the stem being positioned for coaction with the magnetic element against the shoulder to hold the brush in projected use position.

4. An applicator as in claim 3 in which the magnetic element against the shoulder comprises a flanged tube polarized axially and the flange engages the shoulder.

5. An applicator as in claim 3 in which a retainer engages the wall of the enlarged passage portion, the last mentioned magnetic element being engaged between the shoulder and the retainer and held in place by the latter.

6. A liquid applicator of the retractable brush type comprising a hollow container having a neck formed with an outlet through which liquid is dispensed from the interior of the container, a tubular nonmagnetic nozzle body fast to the container and having an axial through passage, the passage having an inner end opening continuous with the neck outlet and an outer end discharge opening, a brush assembly disposed in the nozzle passage, said assembly comprising an elongated stem of nonmagnetic material having inner and outer ends and a brush tuft secured to such outer end of the stem, the brush assembly being axially shiftable in the nozzle passage between a use position in which the brush tuft projects from the discharge opening and a storage position in which the brush tuft is retracted wholly within the nozzle passage, an element of magnetic material substantially completely surrounding the stem and secured to the nozzle at the inner end of the latter, said element being substantially circular in section transverse to the longitudinal axis of the passage, of greater diameter than axial length, and projecting radially into the passage and constituting a liquid flow restriction with an annular clearance space between such element and the stem communicating the inner end opening and the passage, a magnetic element fast on the stem inwardly of the fiow restriction element, one of the magnetic elements being magnetized to attract the other in biasing the brush assembly toward the projected use position, and the nozzle passage being in communication with the interior of the container through the clearance space when the brush assembly is in the projected use position.

7. An applicator as defined in claim 6 in which the nozzle body is formed with a shoulder adjacent its inner end and the flow restricting magnetic element is located against such shoulder.

8. An applicator as defined in claim 6 in which the magnetic element on the stem comprises a sleeve tightly embracing and frictionally held on the stem.

9. An applicator as defined in claim 6 in which the magnetic element on the stem has a circular cross section and the flow restricting magnetic element has a circular center opening of less diameter than such stem element.

10. An applicator as defined in claim 7 in which a retainer is engaged against the nozzle body inwardly of the flow restricting magnetic element and holds the latter against the locating shoulder.

11. An applicator as defined in claim 7 in which the flow restricting magnetic element is in the form of a thin flat washer having a center opening through which the stem is guidingly received and thereby centered in the passage. 7 I i 12. An applicator as defined in claim 10 in which the flow restricting magnetic element has a center opening and the retainer has a center opening smaller than that of the magnetic element, the stem being received through mum @pen n a m sl l sificl is axial movem n s by eg aa mwt w th th c nq 'Refiences Cited in the file of this patent 291,925 Morton ..j. Jan. 15, 1884 8 lockers Oct. 18, 1949 Miller Feb. 24, 1953 Hempel June 30, 1953 Young J an. 25, 1955 Wittnebert Sept. 17, 1957 Hopkins Sept. 2,195 8 Edelstone Jan. 6, .1959 

